The present invention relates to an automatic embedding machine for treating samples for histological examinations.
The preparation of tissue samples for histological examinations is carried out by a number of chemical treatments, and the samples are finally embedded in paraffin. For the chemical treatment, the water contained in the sample is first of all withdrawn from the latter and replaced by stabilizers, dyes and the like. Finally, the sample is embedded in paraffin. This means that the paraffin block can be retained in a stable manner in a receiving means of a microtome. So-called automatic embedding machines, which transport the samples automatically to the various treatment stages, have been developed for the various, successive process steps.
A known automatic embedding machine is described in the document "Jung HISTOKINETTE, Leica Instruments GmbH, List 6008/ND/10/94, October 1994". This automatic embedding machine contains a circular arrangement comprising a plurality of containers for chemicals as well as heatable containers for the wax. The containers are designed to be open at the top. Provided above the containers is a rotatable plate which has a plurality of sample-receiving means. The sample-receiving means can be introduced into the respective containers by virtue of the plate being lowered and rotated. Once a programmable period of time has elapsed, the plate, with the sample-receiving means, is raised again, rotated by a certain amount and lowered again into the next container.
In certain processing steps, it is necessary for a vacuum to be produced in the containers. In the "HISTOKINETTE", such a vacuum can only be produced by separate devices arranged outside the apparatus. These additional devices, however, make the apparatus more difficult to handle. Moreover, in many cases, toxic substances are used for the chemical treatment of the samples. In particular when the samples are changed to the next container, toxic contamination of the surroundings may thus occur. The externally arranged vacuum devices prevent the apparatus from being fully encapsulated.